Fiber optic system with open fiber safety interlock

Abstract

An open fiber safety interlock that disables the light transmitter whenever the cable is disconnected or broken. In one embodiment, a cable containing an optical fiber and an electrical conductor is coupled between a local receiver and a remote transmitter. The remote transmitter transmits a light signal to the local receiver via the optical fiber. The power for the remote transmitter is provided to the remote transmitter via the electrical conductor from a local power supply. Disconnecting or breaking the cable results in a loss of power to the transmitter, thereby halting any further light emissions. Broadly speaking, the present invention contemplates a remote module which implements an open fiber safety interlock. The remote module comprises a transmitter for transmitting light through an optical fiber in a cable, where the cable includes an electrical conductor. The transmitter is configured to transmit light when the cable is coupled to the remote module and a voltage is applied to the electrical conductor. The present invention further contemplates an open fiber safety interlock comprising an electrical conductor, a transmitter, and a power supply. The electrical conductor is part of a cable having an optical fiber for transporting a light beam. The transmitter is configured to provide the light beam, and the power supply is coupled to power the transmitter via the electrical conductor.

What is claimed is: 
     
       1. A remote module which implements an open fiber safety interlock, wherein the remote module comprises a transmitter, for transmitting light through an optical fiber contained in a cable connected to said remote module, wherein the cable includes an electrical conductor configured to connect to a local module comprising a power supply and further configured to power said transmitter through said electrical conductor when said cable is connected to said remote module and to said local module, and wherein the transmitter is configured to transmit light when a voltage is applied to the electrical conductor while the cable is coupled to the local module and to the remote module. 
     
     
       2. The remote module as recited in claim 1, wherein the local module further comprises a receiver configured to received light transmission through said optical fiber when said cable is connected to said local module. 
     
     
       3. The remote module as recited in claim 1, further comprising: a receiver for receiving light from a second optical fiber in the cable; and   a power supply for powering a second transmitter for transmitting light through the second optical fiber in the cable, wherein the power is supplied via a second electrical conductor in the cable when the second fiber is coupled to the second transmitter.   
     
     
       4. An optic system which implements an open fiber safety interlock, wherein the optic system comprises: a cable which includes: a first optical fiber; and   a first electrical conductor;     a remote module which includes a first transmitter for transmitting light through the first optical fiber; and   a local module which includes: a first receiver for sensing light transmitted through the first optical fiber; and   a first power supply configured to supply power to the first transmitter via the first electrical conductor only if the cable is unbroken and properly coupled to both the local module and remote module.     
     
     
       5. The optic system as recited in claim 4, wherein the cable includes a second optical fiber and a second electrical conductor, and wherein the local module further includes a second transmitter for transmitting light through the second optical fiber, and wherein the second transmitter is powered via the second electrical conductor only when the cable is unbroken and coupled at both ends. 
     
     
       6. The optic system as recited in claim 5, wherein the remote module provides an electrical path between the first and second electrical conductors when the cable is coupled to the remote module. 
     
     
       7. The optic system as recited in claim 5, wherein the remote module further includes a second power supply configured to supply power to the second transmitter via the second electrical conductor only when the cable is unbroken and coupled at both ends. 
     
     
       8. An open fiber safety interlock comprising: a first electrical conductor in a cable having a first optical fiber for transporting a first light beam;   a first transmitter configured to provide the first light beam; and   a first power supply coupled to power the first transmitter via the first electrical conductor;   a second electrical conductor in the cable, wherein the cable includes a second optical fiber for transporting a second light beam in a direction opposite the first light beam; and   a second transmitter configured to provide the second light beam, wherein the second transmitter is powered via the second electrical conductor.   
     
     
       9. The open fiber safety interlock of claim 8, further comprising a link which provides an electrical path between the first and second electrical connectors when the first optical fiber is coupled to the first transmitter. 
     
     
       10. The open fiber safety interlock of claim 8, further comprising a second power supply coupled to power the second transmitter via the second electrical conductor.